# LED Annunciator
A quick and dirty little device to inform people you are on the phone or in an
appointment with a traffic light. The state information are generated by a
groupware or messaging application that writes a single letter code into a file.

| Command | Meaning                   |
|---------|---------------------------|
| a       | Turn on all leds          |
| 0       | Turn off all leds         |
| r       | Switch to the red line    |
| g       | Switch to the green line  |
| y       | Switch to the yellow line |

AnnunciatorServer takes the code and sends it via serial port to the device.
Alternatively, similar commands can be send by an infrared remote control.

## Hardware
An Arduino Nano with nine leds on pins D02 - D10. The leds are arranged in three
rows (red, yellow, green) of three leds each.
A YS1838B infrared receiver is connected to D11 and sits on top facing
backwards.

## Software
### led-annunciator
The Arduino code.

### checkLedPins
A program to check the led/pin mapping by turning them on one by one.

### annunciatorServer
The shell script that checks a commandfile and sends single-character
commands to the serial port.
This is useful when the commandfile needs to sit on a network share.

## Room for improvements
- Sometimes the ir receiver starts to send random codes
- As all leds are connected individually, many more commands can be defined.